I'm writing a basic shopping cart and want to avoid the problem with adding items to the cart and then repeatedly hitting refresh in the browser to add the items again. I thought using a RequestDispatcher would solve this problem.
What I do is send the request from the JSP to a servlet that adds the items to the cart and then forwarding the request onto another JSP to show the cart contents. I thought the RequestDispatcher would prevent these problems. Am I doing this wrong?
Originally posted by David O'Meara:
Close, but in these situations it is useful to use response.sendRedirect(), since this forces the client to load the page using a new request, so a reload will just reload the new page and will not result in the item being added multiple times.
Excellent! That works a treat!